1. Field
Embodiments of the present invention generally relate to data communications. In particular, embodiments of the present invention relate to network routing and routing systems, and more particularly to fault-tolerant routing.
2. Description of the Related Art
It is desirable to provide reliable packet delivery between nodes in the network connected by a functional physical path. Interconnected networks vary in the number of redundant paths they provide between nodes. Many conventional routing systems use an active replication technique to provide for failures. With active replication, recovery from failures may be quick, but there is a large overhead in ordinary execution. Active replication uses a redundant structure consisting of two processor resources (e.g., two processors and memory). One problem with active replication is that because all the replicas must be pre-created when the system is running, the processor resources are used wastefully. Another problem with active replication is that because it complicates object management, flexible management and flexible construction are difficult.
Thus, there is a need for systems and methods that provide reliable packet delivery between all pairs of nodes. There is also a need for systems and methods that detect when a fault has occurred and alert the operating system. There is also a need for systems and methods that provide a mechanism to reconfigure a network around faulty areas to ensure quick and reliable packet delivery to all non-faulty areas of the network. There is also a need for systems and methods that are able to reconfigure a network within a short period of time after a failure. There is also a need for systems and methods that provide quick recovery from failure, do not require extra or dedicated hardware as in a hot-standby configuration, and provide for fault tolerant routing without the need to reboot.